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Saeed al-Sahaf writes "Research investment into developing smaller and cheaper chips to process information in disposable health tests has been significant, but they were still reliant on an external power source. The researchers at Singapore's Institute of Bioengineering and Nanotechnology think they have overcome this problem with their latest urine powered battery. From the article "The battery is composed of paper, soaked in copper chloride, sandwiched between layers of magnesium and copper. The whole thing, once laminated in plastic, is just a millimeter thick, and 6cm by 3cm in size." The breakthrough promises a cheap and disposable power source for home health tests."

Why don't they just give us a hand crank? They're more than efficient to power or charge all sorts of small electronics. All we need is a universal plug interface, and we can all be our own emergency backups.

"Pee in this... and turn this."

While they're at it, why doesn't my car have an emergency gear/wheel/crank system that I can connect ot my battery on cold days when my Jolapy won't start?

My dad had an old Model T with an actual engine starting crank. Do it wrong and it could backfire and break your arm. I wouldn't call it convenient either, unless you're some sort of armwrestling champion.

My dad had an old Model T with an actual engine starting crank. Do it wrong and it could backfire and break your arm. I wouldn't call it convenient either, unless you're some sort of armwrestling champion.

Actually I always thought hand cranks were very convenient. Never had a Model T, mostly tractors or stationary engines. You are correct that they can be dangerous, but that has very little to do with convenience. There are many things that are convenient, but not safe.

I'm not sure the size of the engine has as much to do with it as the compression ratio

Absolutely, but there's no reason why a 1.3L Civic couldn't be built with an automatic compression release. I think it's more a matter of demand - nobody actually wants a hand crank to start their car.

1) You can easily crank enough power to start your car, if the mechanism allows you to store up charge over time instead of cranking the engine directly. I don't think the parent poster was describing a direct crank, because the phrase was "connect to my battery", not "connect to my crankshaft".

2) It isn't really that much power, either. I can start my car if my battery is low by pushing it backwards up a very gradual hill for about 5 to 10 meters, then coasting and popping the clutch. I don't even break a

There is one device that does it for primary or backup starting of diesel engines. It has a pull cord like a small gas engine and the first 10 pulls primes the spring and the 11th starts the cranking. It can crank engines up to about 14 liters in size if I recall correctly.I have started large trucks by rolling them as well but as for pushing them anywhere well thats not going to happen (I have managed once to push a smaller truck that weighed about 18000 lbs but only a few feet on level ground). I used my

Because it needs enough power to run the fuel pump, injectors, ecu, ignition coil, ignition system, oil pump, and turn the engine fast. Plus batteries & alternators are plenty reliable enough in most conditions, and less likely to break your arm on a backfire.

Please, stop whining.On Radioshack you can buy a hand crank operated radio.Buy it, strip the radio, and you have a hand crank generator.Build a generator yourself, it's not that hard, it involves magnets and copper wire.

If what you want is standard hand cranks and plugs, and stuff, then it would have to be actually useful. Sorry , it isn't.

If you can rig up a system to spin the alternator (by re-mounting the alternator and using a jacked-up wheel with a belt for a flywheel), you can generate the ~14 volts needed to charge a 12V battery (charge voltage must be higher than discharge voltage - I won't explain that here, look it up), and with no fancy tools, you can recharge the battery enough for a start-up within a couple hours.

That's with NO special tools. If there was a crank system designed into the car, efficiency would increase so much

I wonder if the power comes from the urine, or if urine is acting as an electrolyte that allows the energy stored in the "paper, soaked in copper chloride, sandwiched between layers of magnesium and copper" to be released.

The urine is only the electrolyte, the chemical reaction would be:
Mg + Cu2+ --> Mg2+ + Cu
The battery would also work with pure water. But the whole thing won't be a very "clean" source of energy. Copper chloride is not good for your environment.

I saw that once in a bar near LA: there was a urinal with a 3x3 square hole and the top half of a small paddlewheel behind it. A small sign advised that it was an electronic pissing contest machine, and that men who could turn the paddlewheel the fastest would win a free supersize softdrink (to play again no doubt). A bulb on top of the urinal would go brighter and brighter as the paddlewheel would turn faster.

Near as I can tell, it's new like most everything else is new -- the folks who slept through basic science classes missed how simple galvanic cells work, and now they're surprised by PR from an engineering firm whose employees didn't sleep through science class.

For those just tuning in now, Wikipedia has a nice explanation [wikipedia.org] of this cutting-edge 1780 technology.

For those inclined to experiment, stick a copper rod and an iron rod an inch apart in the dirt in your backyard, and piss in the space between them. Connect wires to the tops of the rods and then to a voltmeter. Wooooeee! You've got current. And you can recharge every time you need to pee.

Of course, technically speaking, you aren't recharging anything. Rechargeable batteries involve a reversible chemical reaction, while a galvanic cell just slowly dissolves its anode and cathode in the intervening electrolyte. For the purpose of providing a feeble current to a disposable medical device, it's not a bad idea. The battery is, however, really old news -- like more than three hundred years old. It's the microelectronics that can take advantage of such weak currents that are the real news, but those aren't exactly at the bleeding edge, either.

The whole thing, once laminated in plastic, is just a millimeter thick, and 6cm by 3cm in size...0.2 millilitres of urine the battery will provide around 1.5 volts, with a maximum power output of 1.5 milli-Watts

So, let's get some facts...Jeeves says [ask.com] that normal humans feel the need to urinate when they hold 150 - 200mL of urine in their bladder. 200mL sounds decent for this math.

200mL / 0.2mL per battery = 1000 batteries that can be charged on a normal fill of urine.

I was noticing the error as well. I was disappointed that the article didn't say how much work (watts*time) could be extracted from a particular volume of urine. Though I would imagine that it might very well vary a lot.

If this thing could be made small enough, it could be put within the <a href=http://en.wikipedia.org/wiki/Urinary_bladder> bladder</a> (1.1 to 1.3 litres) to work as a permanent machine. It could talk using 802.11b and bluetooth, be its own 'hotspot' so that a human mesh can be made. You wouldnt need to carry a wallet at all. It could also check your health that way. I wonder if it can be used with a plug and an actuator to 'hold it' for you when you really have to go and have nowhere to go.

Nothing in Urine is converted. The urine acts as an electrolyte between sheets of copper and magnesium. Actually, urine doesn't even act as the electrolyte, the copper chloride impregnated in the paper does. The urine just dissolves the copper chloride and completes the circuit. Distilled water could be used here just fine.

I'm afraid this post will get lost in all of the pee-pee jokes, but what the hell. I don't see what function urine serves in these batteries. I didn't think urine was all that energetic. The article says these things can output a maximum of 1.5 mW at 1.5 V, so why not just use a tiny alkaline battery? A very tiny battery could be produced for a few cents and they have shelf lives of several years. I just don't see why you need to involve urine at all (other than the fact that it gets your research in t

On more serious terms:If urine energy would become too popular, we can expect worldwide beer shortage and families with more children opening energy farms.Unfortunatelly, there's no action without reaction

I'm not a chemist, but I would say "not much", since I am a physician. Urine is pretty much just filtered blood, with essential stuff reabsorbed as much as possible, and concentrated according to the water needs of your body. A few ions are actively secreted by the kidney, but not at amazing concentrations. You'd chemically burn the tip of your penis off after you urinate, otherwise!

My guess is that the urine just acts as the
electrolyte. It doesn't have to be extremely acidic to be a usable electrolyte. Normal urine has a pH of around 6, but the pH can be as low as 4 or as high as 8. The main mechanism used by the body to maintain pH balance is the excretion of acidic or alkaline urine. Diet has a signficant effect. Vegetarians tend to have more alkaline urine, people who eat a lot of meat more acidic urine. Starvation and dehydration increase the acidity of the urine. Also, decrease